<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>圣杯布局</title>
</head>
<style>
    .father{
        padding: 0 300px 0 200px;
    }
    .son_left, .son_center, .son_right{
        position: relative;
        float: left;
        height: 300px;
    }
    .son_center{
        width: 100%;
        background-color: palevioletred;
    }
    .son_left{
        width: 200px;
        left: -200px;
        margin-left: -100%;
        background-color: papayawhip;
    }
    .son_right{
        width: 300px;
        margin-right: -300px;
        background-color: purple;
    }
</style>
<body>
    <div class="father">
        <div class="son_center">这是中间的盒子</div>
        <div class="son_left">这是左边的盒子</div>
        <div class="son_right">这是右边的盒子</div>
    </div>
</body>
</html>